BIO 168 CH.2 (PT.1) Flashcards
what is matter composed of?
atoms
96% of human body weight contains what?
hydrogen, oxygen, carbon, and nitrogen
what atom has a +1 charge, located in the nucleus, and 1 AMU
protons
what atom has a -1 charge, arranged AROUND the nucleus, and atomic mass is negligible (so small its not important)
electrons
what atom has no charge, located in the nucleus, and 1 AMU
neutrons
what is the atomic number of an element?
number of protons in every atom of that element
what is atomic mass
the number of protons AND neutrons in an atom of element
of protons (p)=
atomic number
of neutrons (n)=
atomic mass minus atomic number
of electrons (e)=
= to atomic number in a neural atom
isotopes are
atoms with the same element but with different neutrons
ex. C-12 has 6 neutrons, C-13 has 7 neutrons
an Ion is a
charged atom, they either lost or gained a bit. has an electrical charge
cations have a
positive charge
anions have a
negative charge
a ionic bond is when a
cation and anion are attracted to each other by opposite charges
each atom shared are called
covalent bonds
isomers are
molecules with the same numbers, and atoms but in a different order
C-H bonds are (Carbon and Hydrogen)
nonpolar
2 atoms with equal electronegativity do what
they share electrons equally and make a nonpolar covalent bond
2 atoms with unequal electronegativity do what
they share electrons unequally and make polar covalent bonds
O=O, C-H, and C-C are examples of what kind of bond
nonpolar
O-H, C=O, N-H, N-O are examples of what kind of bond
polar
molecules with both nonpolar and polar portions are called
amphipathic
Functions of water in the body are
transportation, lubrication, cushioning, excretion, and thermoregulation
